CMV: Praying for someone to get a disease is not wrong.

I was talking to one of my coworkers about religion and he said that in one of his old congregations, when a pastor left to be a Methodist, the head ministers would pray for the old pastors children to get sick and die so that he would realize that the church he is going to is bad and that he should return to their church. My coworker said that this is not wrong and I told him that it is because praying for someone to die is not right and its just an excuse for people to be shitty. What do you think about the situation, should the ministers be in the wrong for praying for children to die or not. I believe that they are in the wrong while my coworker does not believe that they are. Try to change my view, please!